The present invention relates to a ski boot with improved lateral support.
The problem of transmitting the efforts of the foot to the ski in an efficient manner, so as to achieve optimum control of said ski, is nowadays strongly felt for ski boots.
In this regard, some solutions are known, related or aimed directly at these problems. Among them, mention should be made of U.S. Pat. No. 3,545,103 which discloses a ski boot closure device comprising a metallic lateral plate that laterally surrounds the outer part of the foot and with which a cuff is rotatably associated.
Although this plate stiffens the boot to a given extent, it nonetheless does not provide optimum transmission of the efforts from the foot to the ski. In current skiing technique, the ski is in fact controlled by the inner part of the leg and of the foot, and this is therefore the part of the ski boot that is most intensely stressed during skiing and that transmits the efforts.
The placement of the plate on the outer side in the prior patent is therefore not effective for precise ski control.
Italian patent no. 1,051,302 discloses a ski boot made of plastics which is substantially constituted by two shells that mutually overlap along lateral joining lines and are kept in this closed position by fastening means.
This solution, which has the purpose of providing a method for manufacturing the boot in a mold without back drafts, entails the presence of parts that allow to adapt it to devices for binding to the ski, as well as a framework formed by thick and rigid ridges and by thin flat portions that connect said ridges.
Although it partially solves the described technical problem, as the ridges affect both the outer side and the inner side of the boot, even this solution does not allow to achieve optimum transmission of efforts from the foot to the ski, because in controlling the ski, the efforts are discharged approximately at the region of the plantar arch. In the solution illustrated in the patent, this region is not affected by the rigid ridges but by the thin flat portions.
Furthermore, the arrangement and shape of the ridges in any case causes the boot to be subject to slight deformations during sports practice that help to reduce the optimum transmission of efforts to the ski.
Italian Patent application no. 82513 A/87, filed on Feb. 25, 1987 in the name of this same Applicant discloses a ski boot which is constituted by a semirigid innerboot with which it is possible to associate at least one first rigid element, which partially surrounds the lower and lateral regions of the semirigid innerboot. Two second rigid elements are arranged at the sides of the semirigid innerboot and are rotatably associated with the first rigid element and articulated to it.
This solution, too, despite partially overcoming the drawbacks described above, is not optimum as regards effort transmission, because the presence of articulations does not allow, in any case, highly efficient transmission of efforts for optimum ski control. In fact, plays generate at the articulation between the first element and the second rigid elements, also due to wear and deformations, and tend to reduce the efficiency of the transmission.
International Patent WO 92/16120 claiming an Austrian priority, no. A 631/91 dated Mar. 21, 1991, discloses a ski boot which comprises a support that can be fixed to the leg above the ankle, is connected to the sole by means of a bar, and is shaped like a stencil that can be fixed and acts together with at least one part of the shell. The stencil-like support is connected to the bar, preferably at a level located between two closed portions of said stencil-like support, by means of a bracket that approximately comprises half of the circumference of the leg.
Even this solution is not optimum as regards the transmission of efforts directly to the ski, because it is again constituted by a plurality of elements that can be coupled to each other, to the shell and to the quarter of the boot.
It is also noted that the bar is laterally provided with two arms, the lower parts thereof are associated at the heel region of the shell.
This solution is not optimum for the transmission of efforts to the ski, because this arrangement produces moments that can open out the curve or cause a self rotation in extreme circumstances.
As regards the described technical problem, this same Applicant filed an Italian application, no. 82601 A/90, on Jul. 23, 1990, claiming a quarter associated with the shell, and at least one slot being formed on said quarter at the lateral regions. The slot has the same angle, or a different angle, with respect to at least one guide formed on the shell, and at least one slider is slidingly associated between the slot and the guide.
Even this solution has drawbacks due to the fact that the quarter is laterally pivoted to the shell by means of studs or by means of a crosspiece arrangeable at a seat formed transversely and below the sole.
On one hand, in fact, the quarter does not have particular lateral support characteristics considering the material of which it is usually made, and on the other hand its tilting does not allow optimum transmission of the efforts to the ski, as the function related to the variation of the inclination that can be achieved for the quarter is privileged.